Title:
コンデンサマイクロフォン
Document Type and Number:
Japanese Patent JP4383695
Kind Code:
B2
Abstract:
This present invention is related to a capacitor microphone. Capacitance change of a microphone unit without polarization voltage is converted to a digital signal to obtain a sound signal in order that the microphone restricts noise and the productivity of the microphone is increased. The capacitor microphone comprises a first oscillator 2 which outputs a sound signal varying frequency in response to capacitance change of the microphone unit 1 , a second oscillator 3 which outputs a tracking signal varying frequency because of a control voltage CV, a phase comparator 4 comparing phases of the sound signal and the tracking signal to output lead or lag signal, and an adder-subtracter 14 outputting digital sound data. An adding-pulse signal and a subtracting-pulse signal, which are obtained by the logical product of the lead-phase or lag-phase signal and clock pulses, are inputted to the adder-subtracter 14.
Inventors:
Hiroshi Akino
Application Number:
JP2001205760A
Publication Date:
December 16, 2009
Filing Date:
July 06, 2001
Export Citation:
Assignee:
Audio Technica Co., Ltd.
International Classes:
H04R3/00; H04R19/04; H04R1/04
Domestic Patent References:
| JP2001505719A | ||||
| JP9107285A | ||||
| JP8506952A | ||||
| JP7095094A | ||||
| JP3066199U |
Attorney, Agent or Firm:
Takuya Ohara